Sorptive removal and recovery of nickel(II) from an actual effluent of electroplating industry: Comparison between Escherichia coli biosorbent and Amberlite ion exchange resin

The removal and recovery of nickel(II) from wastewater of an electroplating factory was investigated using the waste Escherichia coli biomass as the biosorbent. The results were compared with those from using Amberlite IRN-150 as a commercial sorbent resin. The resin showed better performance with a q_max value of 30.48 mg/g compared to 26.45 mg/g for the biomass, as predicted by the Langmuir isotherm model. Kinetic experiments revealed that the biosorption equilibrium was attained within 15 min. In the recycling of the sorbents, the desorption of nickel(II) from Amberlite was only 50%, which is too low for the adsorption performance of the resin to be maintained at an economic level in subsequent cycles. In contrast, the biomass exhibited reasonable adsorption-desorption performance over three repeated cycles. The capability for repeated use of the sorbent over several cycles and for recovery of the metal ions is the main advantage of the waste biomass.